1. Technical Field
A cleaning solution is disclosed for removing photoresist resins used in cleaning semiconductor substrates during the last process after development. More specifically, a cleaning solution for removing photoresist is disclosed that comprises water (H2O) as main component, one or more surfactants as additive selected from the group consisting of polyoxyalkylene compounds, a salt of alcohol amine of Formula 1 and hydrocarbon compounds having carboxylic acid (—COOH) group, a salt of alcohol amine of Formula 1 and hydrocarbon compounds having sulfonic acid (—SO3H) group, polyethylene glycol compounds, compounds of Formula 3, compounds having a molecular weight ranging from 1000 to 10000 including repeating unit of Formula 4 and polyether denatured silicon compounds and alcohol compounds.
2. Description of the Related Art
As devices are getting minute, photoresist patterns have a higher aspect ratio (i.e. the ratio of the thickness of photoresist, or height to the linewidth of formed pattern).
When the height of formed photoresist patterns goes beyond critical height, capillary force exceeds elasticity of photoresist, thereby resulting in erosion of patterns during a cleaning process
In order to overcome this problem, adhesive force between underlying layers and photoresist is enhanced by increasing inner elasticity of photoresist or decreasing surface tension thereof.
Generally, a method of forming photoresist patterns on semiconductor substrates comprises the steps of:                forming an underlying layer on a semiconductor substrate;        forming a photoresist film on the underlying layer; and        forming a photoresist pattern by exposing a portion of the underlying layer using exposing and developing processes.        
Here, in case of a positive photoresist film, a photoresist film of an exposing region is removed by developer and then a photoresist pattern is formed.
As described above, after the photoresist pattern is developed, the remaining photoresist film on the semiconductor substrate is removed by dispersing distilled water to the semiconductor substrate from a top portion of spin device. Here, the pattern is eroded due to high surface tension of distilled water.
The conventional cleaning solution comprised anion surfactant in order to prevent the collapse of photoresist patterns having high aspect ratio. For example, U.S. Pat. No. 6,451,565 describes that the cleaning solution included anion surfactant having fluorine and deionized water to prevent the collapse of such patterns